HOW THE DILATANCY OF SOILS AFFECTS THEIR BEHAVIOUR

The relationships between the friction angle, dilation angle, density and pressure in a granular material are explored. The link between friction and dilation is well established, but quantitative expressions for the dependance of dilation on density and pressure are less well known. A new relationship based on the concepts of Critical State Soil Mechanics is suggested. The types of problem in which dilation plays an important role are then examined, and it is seen that dilatancy increases in significance for heavily constrained problems. The influence of dilation on the capacity of piles is treated in more detail. Additional topics treated include the generalization of dilation expressions